Digging apparatus

ABSTRACT

An improvement in an apparatus for creating repetitive explosions from an outlet of a combustion chamber by actuating a digging assembly by the explosive pressures to loosen and break up hard materials. The use of piston-driven digging teeth for loosening and breaking up material formations both prior to and simultaneously with material displacement by repetitive explosive blasts. An apparatus positioning locking assembly including a piston-driven pin actuated by the repetitive explosive blasts into position for holding the apparatus in position and which is actuated either prior to or simultaneously with the material displacement blasts and digging assembly actuation.

an: 3 9 574 t M l [72] Inventor Thomas J. Hogan San Antonio, Tex. [21Appl. No. 823,626 [22] Filed May 12,1969 [45 Patented Apr. 13, 1971 [73]Assignee H. B. Zachry Company San Antonio, Tex.

[54] DIGGING APPARATUS 5 Claims, 4 Drawing Figs.

[52] US. (I 299/37, 299/ l 3 [51] Int. Cl E21c 29/00 [50] Field ofSearch 299/13, 36, 37, 67, 69, 70, 81; 173/59, 73; 175/93, 14

[56] References Cited UNITED STATES PATENTS 1,840,002 1/1932 Wallis299/67 2,327,619 8/1943 Brown et al 173/59 2,574,103 11/1951 Hefner173/59X 3,375,596 4/1968 Bacquie 299/37X 3,461,577 8/1969 Clark et al.299/13X Primary Examiner-Ernest R. Purser Attorneys-James F. Weiler,Jefferson D. Giller, William A.

Stout, Paul L. De Verter 11, Dudley R. Dobie, Jr. and Henry W. HopeABSTRACT: An improvement in an apparatus for creating repetitiveexplosions from an outlet of a combustion chamber I PATENTED APR 1 31971SHEET 1 OF 2 ffza/nau 4/ hqyaw BY a ada zm A 7' 7' 0/17/75 VJ BACKGROUNDOF THE INVENTION US. Pat. No. 3,46 l ,577 entitled Method of andApparatus for Displacing Materials, discloses the use of combustion heatand pressures from the repetitive firing of a hydrocarbon fuel/airmixture in a combustion chamber for displacing materials by therepetitive explosive blasts. However, rocky or hard soil conditions ormaterials offer a great deal of resistance to the optimum penetrationand positioning of the exhaust outlet of the combustion chamberdisclosed in the above mentioned patent application.

SUMMARY The present invention is directed to providing accessories foruse with and actuated by the repetitive explosions from the outlet ofthe combustion chamber by the ignition of fuels therein to loosen andbi'eak up the soil or materials desired to be moved, separately from,prior to, and simultaneously with the displacement of the material bythe explosive blasts from the combustion chamber.

It is one object of the present invention to provide in combination withan apparatus for creating repetitive explosions froman outlet of acombustion chamber by the ignition of hydrocarbon fuel/air mixtures, 'asoil digging assembly having a piston in communication with and actuatedfrom the combustion chamber with digging means connected to the pistonand positioned to engage the material for breaking up and loosening thematerial.

A further object of the present invention is the provision of adoor-type piston in the outlet of a combustion chamber hinged at itsupper side and having a plurality of ripping teeth on the outsidewhereby on actuation the material is engaged and loosened by the rippingteeth as well as displaced as the explosive blast moves past the doorand out of the explosion chamber outlet.

A still further object is the provision of a piston door incommunication with a combustion chamber which is convexed in crosssection to increase the leverage of the explosive force on the door forincreased penetration of the digging assembly.

Yet a still further object of the present invention is the provision ofa positioning locking assembly attachment which provides a second pistonin communication with the combustion chamber with a holding pinconnected to the piston and positioned to be extended downwardly intothe material or soil as the second piston is actuated to hold theapparatus in position as the material is broken up or displaced, andalso including'means for providing for the actuation of the secondpiston at a time prior to actuation of the digging or displacementmechanism to hold the entire apparatus firmly in place.

Yet a still further object to the present invention is the provision ofa soil ripping assembly or attachment to the outlet of acomhustioncharnber having a door connected at an upper side andpositioned in the outlet of the combustion chamber to form a pistontherein which is actuated by the repetitive ignition of a hydrocarbonfuel/air mixture in the chamber in which a plurality of ripper teeth areconnected to the door and extend downwardly and are directed forwardlybelow the outlet and into the soil for loosening the soil.

BRIEF DESCRIPTION OF THE DRAWING In the attached drawings, likecharacter references refer to like parts throughout the several views inwhich:

FIG. 1 is a cross-sectional elevational view, partly schematic,illustrating one embodiment of the present invention prior to anexplosion in the combustion chamber,

FIG. 2 is a view similar to FIG. 1, illustrating the apparatus of FIG. Iin position afteran explosion in the combustion chamber,

FIG. 3 is a cross-sectional elevational -view, partly schematic,illustrating the use of a chisel for penetrating hard 2 formations andto provide suitable penetration for positioning of the materialdisplacement explosive outlet, and

' FIG. 4 is a cross-sectional elevational view, partly schematic,illustrating another embodiment of the present invention used forripping the material.

DESCRIPTION OF THE PREFERRED EMBODIMENT By way of example only, thepresent invention will be described in use for displacing earth andsoil, but it is to be understood that the present apparatus mayconveniently be used for loosening, breaking up and displacing many andvarious other types of material.

Referring now to the drawings and particularly to FIGS. 1 and 2, thenumeral 10 generally indicates the apparatus of the present invention inuse in moving a material 1] such as soil and generally includes anexplosion cell or combustion chamber 12 which may be periodically movedagainst the soil 11 to be displaced by a suitable vehicle (not shown) toprovide an explosive force through the outlet 13 of the combustionchamber 12 against the soil 11 to displace and move the soil. Thecombustion chamber 12 is charged with a suitable combustion mixture forcreating an explosion therein, preferably the chamber l2 is charged withan air/fuel mixture, the air being provided through an air inlet 16, thefuel, preferably a hydrocarbon fuel, being provided through an injectionnozzle 20 to provide an air/fuel mixture at the desired pressure andair/fuel mixture ratio. Combustion is initiated by a suitable ignitionsource 22 for creating an explosive force from the combustion chamberoutlet 13 which is directed against the soil 11. The foregoing isgenerally described in the-above-mentioned patent application.

However, the displacement of the soil 11 by explosions may be moreefficiently utilized by the optimum penetration and positioning of theoutlet 13 against the soil 11 by providing a digging assembly,particularly in hard rocky soils and other relative adamantinematerials. The present improvement relates to the use of a diggingassembly such as ripping tools or penetration pins or chisels which aredriven directly by the explosive pressures from the combustion chamber12 to loosen and break up the material 11 by the repetitive explosiveblasts. Thus, a plate or door 30 is provided which is pivotallyconnected at its upper side such as to a pin 32 and is positioned in theoutlet 13 of the combustion chamber 12 toform a piston therein. Aplurality of digging teeth such as ripper teeth 34 are provided on theoutside of the door 30 for engagement with the soil 11. Thus, when anexplosive blast is applied to the back of the door 30 the door will moveout of the outlet 13 moving the teeth 34 against the soil 11 to break upand loosen the soil and the explosive blast explodes out of the outlet13 and beneath the soil 11 which has been now loosened and broken up fordisplacement by the exhaust blast, as best seen in FIG. 2. Penetrationinto hard materials such as hard soils or rock-laden formations may befacilitated by one or more firings of the combustion chamber 12 at lowerpressures below which would prove optimum for a mass displacement of thematerials. The lower pressure firings would jar the door 30 and teeth 34forward one or more times thereby allowing the apparatus 10 to move to abetter position with the outlet 13 in full contact against the soil 11to be displaced so as to be more effective for mass displacement of thematerial by the explosive exhaust. The explosive action acting on theback 36 of plate 30 provides an improved leverage around the pivot pin32 for increasing the force applied against the material 11 and also forforcing proportionally greater amounts of the explosiveexhaust out nearthe base or bottom of the plate 30 which also increases the leverage andincreases the displacement action on the loosened material.

As explosive blasts are released from the outlet 13 of the combustionchamber 12, there is a tendency for the apparatus 10 to be thrustbackwardly. Therefore, a position locking assembly may be provided ifdesired which may include a second piston 38 in communication with thecombustion chamber through a passageway 40 and to which is connected aholding pin 42 which is positioned to extend downwardly and intoengagement with the soil or material 11 as the piston 38 is actuated.Pin 42, as best seen in FIG. 2, will thus penetrate hard surfaces andgive the ripping door 30 a finn support from which to push. Spring 44 isprovided to act as a retracting means for the piston 38 after anexplosion in which the force behind the piston is vented back to thecombustion chamber 12.

Valve 50 normally is held in a seated position by the spring 52 andperforms the function of sealing ofi the combustion chamber 12 from theoutlet 13 until a predetermined buildup in the explosive force in thechamber occurs after which the valve 50 opens allowing the high pressureand the temperature gases to move out the outlet 13 and rupture the soil11. However, the valve 50 also performs an additional function in thatit provides a timing means to allow the actuation of the positionlocking assembly piston 38 at a time prior to the actuation of the platepiston 30 thereby insuring that the apparatus will be secured in placeprior to the release of the explosive force through the outlet 13 so asto hold the apparatus 10 in place and insure that the full impact fromoutlet 13 will be exerted on the soil 11.

Of course, various modifications may be utilized to provide varioustypes of digging assemblies such as ripping tools or penetration pins orchisels driven directly by the explosive pressures from the chamber 12to loosen and break up the formation either without, prior to, andsimultaneously with the material displacement from the chamber 12. F168.3 and 4 illustrate modifications according to the present invention,letters a and b being applied to parts corresponding to those in FIGS.1-2 inclusive, for convenience of reference. Thus, FIG. 3 illustrates inthis embodiment a piston 56 which is exposed to the combustion chamber12a drives a penetration rod or chisel 58 outwardly and forwardly of thefront point 60 of the combustion chamber for breaking up the materialformation adjacent the leading edge 60 to aid in the proper penetrationand positioning of the outlet 13a of the combustion chamber to provide amore efficient penetration of the material 11a by the outlet 1130.

Referring now to FIG. 4 the material displacing apparatus 10b ispreferably towed by means of supports 62. The outlet 13!; of thecombustion chamber 12b is carried above the material 1117 which is to beripped or broken and excavation of the soil 11b will be performed by anysuitable means at a later step in the operation. In providing only aripping operation, a piston 64 is provided hinged at its upper side to apin 66 and mounted in the outlet 13b and thus in communication with therepetitive explosions from the combustion chamber 12b and carries aplurality of ripping teeth 68 which are connected to the piston door 64and extend downwardly and forwardly below the outlet 13!) and into thesoil or material 11b for ripping and breaking up the material.Preferably, the apparatus 10b is towed by suitable means (not shown) bythe support 62 so that the prime mover is not required to travel overits own spoilage.

The present invention, therefore, is well adapted to carry out theobjects and attain the ends and advantages mentioned as well as othersinherent. therein. While pre ently preferred embodiments of theinvention are given for the purpose of disclosure, numerous changes inthe details of construction, and arrangement of parts will readilysuggest themselves to those skilled in the art and which are encompassedwithin the spirit of the invention and the scope of the appended claims.

lclaim:

1. In combination with an apparatus for displacing material having acombustion chamber for creating and applying a repetitive explosiveforce against the material, a digging assembly comprising:

a piston in communication with the combustion chamber,

said piston including a door hinged at one side, digging means connectedto one side of the piston remote from the combustion chamber andpositioned to engage the material, said digging means including aplurality of ripping teeth for penetration and loosening of hardmaterials, and

means limiting the travel of the piston and the digging means.

2. In combination with an apparatus for displacing material having acombustion chamber for creating and applying a repetitive explosiveforce against the material, a digging assembly comprising:

a piston in communication with the combustion chamber,

digging meansconnected to one side of the piston remote from thecombustion chamber and positioned to engage the material,

means limiting the travel of the piston and the digging means,

a second piston in communication with the combustion chamber, and

a pin connected to one side of the piston remote from the combustionchamber and positioned to be extended downwardly as the piston isactuated thereby acting to hold the apparatus in position when thedigging assembly is actuated.

3. The apparatus of claim 2 including valve means sealing off thecombustion chamber from the first piston until the second piston hasbeen actuated.

4. In combination with an apparatus displacing material by applyingcombustion pressure from the repetitive ignition of a hydrocarbonfuel/air mixture from the outlet of a combustion chamber against thematerial, a digging assembly comprising:

a door pivotally connected at its upper side and positioned in theoutlet of the combustion chamber to form a piston therein,

a plurality of ripper teeth connected to the door on the side remotefrom combustion chamber for engaging the material to be broken up,

a piston locking assembly including:

a second piston in communication with the combustion chamber, and

a pin connected to the piston on the side remote from the combustionchamber and positioned to be extended downwardly as the second piston isactuated thereby acting to hold the apparatus in position when thefuel/air mixture is ignited, and

valve means sealing off the combustion chamber from the door until thesecond piston has been actuated.

5. in combination with an apparatus for creating repetitive explosionsfrom an outlet of a combustion chamber by the ignition of a hydrocarbonfuel/air mixture, a soil ripping assembly comprising:

the outlet of the combustion chamber being positioned about the soil,

a door pivotally connected at its upper side and positioned in theoutlet of the combustion chamber to form a piston therein,

a plurality of ripper teeth connected to said door and extendingdownwardly and directed forwardly below said outlet and into the soilfor loosening the soil, and

means for towing said apparatus across the soil.

1. In combination with an apparatus for displacing material having acombustion chamber for creating and applying a repetitive explosiveforce against the material, a digging assembly comprising: a piston incommunication with the combustion chamber, said piston including a doorhinged at one side, digging means connected to one side of the pistonremote from the combustion chamber and positioned to engage thematerial, said digging means including a plurality of ripping teeth forpenetration and loosening of hard materials, and means limiting thetravel of the piston and the digging means.
 2. In combination with anapparatus for displacing material having a combustion chamber forcreating and applying a repetitive explosive force against the material,a digging assembly comprising: a piston in communication with thecombustion chamber, digging means connected to one side of the pistonremote from the combustion chamber and positioned to engage thematerial, means limiting the travel of the piston and the digging means,a second piston in communication with the combustion chamber, and a pinconnected to one side of the piston remote from the combustion chamberand positioned to be extended downwardly as the piston is actuatedthereby acting to hold the apparatus in position when the diggingassembly is actuated.
 3. The apparatus of claim 2 including valve meanssealing off the combustion chamber from the first piston until thesecond piston has been actuated.
 4. In combination with an apparatusdisplacing material by applying combustion pressure from the repetitiveignition of a hydrocarbon fuel/air mixture from the outlet of acombustion chamber against the material, a digging assembly comprising:a door pivotally connected at its upper side and positioned in theoutlet of the combustion chamber to form a piston therein, a pluralityof ripper teeth connected to the door on the side remote from combustionchamber for engaging the material to be broken up, a piston lockingassembly including: a second piston in communication with the combustionchamber, and a pin connected to the piston on the side remote from thecombustion chamber and positioned to be extended downwardly as thesecond piston is actuated thereby acting to hold the apparatus inposition when the fuel/air mixture is ignited, and valve means sealingoff the combustion chamber from the door until the second piston hasbeen actuated.
 5. In combination with an apparatus for creatingrepetitive explosions from an outlet of a combustion chamber by theignition of a hydrocarbon fuel/air mixture, a soil ripping assemblycomprising: the outlet of the combustion chamber being positioned aboutthe soil, a door pivotally connected at its upper side and positioned inthe outlet of the combustion chamber to form a piston therein, aplurAlity of ripper teeth connected to said door and extendingdownwardly and directed forwardly below said outlet and into the soilfor loosening the soil, and means for towing said apparatus across thesoil.